\documentclass[spanish,a4paper,11pt,landscape]{article}

\usepackage[spanish,activeacute]{babel}
\usepackage{graphicx}
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\begin{document}


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\Large Gr'aficos de funciones de $\mathbb{R}^2 \rightarrow \mathbb{R}$ (o sea de Campos Escalares)\\
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\fbox{\includegraphics[width=13cm]{campoEscalar1}}
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\fbox{\includegraphics[width=13cm]{campoEscalar2}}

\newpage
\noindent
\Large Gr'aficos de funciones de $\mathbb{R}^2 \rightarrow \mathbb{R}$ (o sea de Campos Escalares)\\
\noindent
\fbox{\includegraphics[width=13cm]{campoEscalar3}}
\noindent
\fbox{\includegraphics[width=13cm]{campoEscalar4}}

\newpage
\noindent
\Large Curvas de nivel de funciones de $\mathbb{R}^2 \rightarrow \mathbb{R}$\\
\noindent
\fbox{\includegraphics[width=13cm]{curvaDeNivel1}}
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\fbox{\includegraphics[width=13cm]{curvaDeNivel2}}
\noindent


\newpage
\noindent
\Large Curvas de nivel de funciones de $\mathbb{R}^2 \rightarrow \mathbb{R}$\\
\noindent
\fbox{\includegraphics[width=13cm]{curvaDeNivel3}}
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\fbox{\includegraphics[width=13cm]{curvaDeNivel4}}
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\fbox{\includegraphics[width=13cm]{curvaDeNivel5}}
\noindent
\fbox{\includegraphics[width=12cm]{curvaDeNivel6}}

\end{document}
